China is not trying hard (to put it mildly) to enforce UN-mandated sanctions on North Korea, according to some intrepid New York Times reporters who visited the North Korea-China border recently:

When the United Nations adopted tougher sanctions against North Korea last month to punish it for its nuclear weapons program, it was understood that they would have little effect without strong cooperation from China, North Korea’s largest trading partner.

If recent trade here is any indication, that cooperation has been spotty at best.

Cross-border trade, legal and illegal, flows pretty much as usual, and seems to be largely unhindered by the new rules, traders and local officials said.

One of the toughest components, a requirement that countries inspect all cargo entering or leaving North Korea for banned goods, is not enforced here.

Interesting—especially because the United States has been trumpeting its success getting China on-board with the tough measures. The sanctions were a response to North Korea’s missile activity and nuclear test, and they were enthusiastically welcomed by Japan and South Korea, in particular. Yet it looks like, as in the South China Sea, Beijing doesn’t seem particularly intimidated by U.S. demands after all.

If White House opinion doesn’t weigh on China’s mind, the distance North Korea has put between Beijing and its East Asian rivals, South Korea and Japan, might. In Washington for the Nuclear Security Summit, Prime Minister Shinzo Abe and President Park Geun-hye pledged not to let old grievances keep them for working together to address North Korea.

As we’ve said all along, when North Korea misbehaves, China loses. But whether it loses big or loses small is, to a great extent, in Washington’s hands. If the U.S. can’t compel China to cooperate with the sanctions regime, Beijing can weasel its way out of a tough spot. Meanwhile, Washington loses credibility with key allies in Japan and South Korea.